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41.
A sheathless interface based on a total consumption micronebulizer operating at flow rates in the range 0.5-7.5 microL min(-1) was developed between capillary HPLC and ICPMS. It allowed the efficient nebulization and transport into the plasma of mobile phases containing up to 100% organic solvent without either cooling the spray chamber or oxygen addition. The coupled system was applied to selenopeptide mapping in a protein fraction isolated from a selenized yeast extract. The detection limits were 150 (80Se) and 200 fg (82Se) for a quadrupole instrument with and without a collision cell, respectively, which is a factor 100-150 less than that reported elsewhere for HPLC-ICPMS. The minimal peak broadening ( approximately 5 s at the half-height) allowed baseline resolution of a mixture containing more than 30 selenopeptides, many of which could not be separated using the conventional HPLC-ICPMS coupling.  相似文献   
42.
We have investigated a new approach to efficiently find a novel inhibitor against a serine protease (i.e. an activated coagulation factor X, FXa) by using de novo design programs and the X-ray crystal structure of the target enzyme. FXa is a coagulant enzyme that generates thrombin (a serine protease) and participates in both intrinsic and extrinsic coagulation pathways. We adopted multiple copy simultaneous search (MCSS) and CAVEAT linker search techniques, which disclosed a novel FXa inhibitor (T01312) consisting of two binding moieties (the benzamidinyl and adamantyl groups) and a linker unit (the carboxybenzylamine group). The inhibitory activity of T01312 against FXa was determined to be a small K(i)-value of 48nM, which is two orders of magnitude smaller than that against thrombin. An X-ray crystal analysis of T01312 complexed with trypsin (an analogue of FXa) and docking studies of T01312 with trypsin and FXa showed that: (i) the benzamidinyl group is a predominant binding moiety in the anionic pocket (S1 site) with an asparatic acid residue; (ii) a hydrophobic pocket (S4 site) is the binding site of the adamantyl group; (iii) the carboxylate group of the linker contributes to the selectivity for FXa against thrombin. Thus, the combination of the knowledge of the X-ray crystal structure of the target molecule with MCSS and CAVEAT linker search techniques proved to be an effective hit-finding method that does not require the screening of huge compound libraries.  相似文献   
43.
This paper describes key aspects of remote service invocation in federations of OSGi containers. It refers to the OSGi Remote Service Admin specification and describes its efficient implementation over message‐oriented middleware. Scalability problems of several different approaches to implementation are identified, and a solution in a form of innovative Remote Service Admin model extension is proposed. The extension, named On‐demand Remote Service Admin, is analyzed and validated in the context of a motivating scenario. Validation includes performance and scalability evaluation, which confirms that all assumed requirements have been satisfied by the constructed prototype. Finally, the presented research is compared with related works. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
44.
The asymptotic stabilisation problem of a class of large-scale interconnected systems is considered, where the non-linear interconnections between subsystems satisfy quadratic constraints that are functions of the whole system's state vector. A decentralised combined observer-controller compensator is proposed and analysed, where the subsystems’ state vectors are estimated using local sliding mode observers. The closed-loop system driven by the proposed decentralised compensator is guaranteed to be asymptotically stable subject to two conditions that are easily verifiable. Simulation results illustrate the effectiveness of the proposed decentralised combined observer-controller compensator.  相似文献   
45.
In this paper we show that properties of non-linear time structures have not been studied enough. Axioms forcing the existence of a branching point in a branching area of a structure are presented for various classes of structures. We show also that the classical Dedekind continuity axiom does not work well in non-linear structures and we suggest stronger versions. Finally, some interdependencies between the axioms presented are proved.  相似文献   
46.
The carbon material was modified by RF plasma with various reactive gases: O2, Ar and CO2. Physicochemical properties of the final carbon products were characterized using different techniques such as gas adsorption method and XPS. Plasma modified materials enriched in oxygen functionalities were investigated as electrodes for supercapacitors in acidic medium. The electrochemical measurements have been carried out using cyclic voltammetry, galvanostatic charge/discharge and impedance spectroscopy. The electrochemical measurements have confirmed that capacity characteristics are closely connected with a type of plasma exposition. Modification processes have an influence on the kind and amount of surface functional groups in the carbon matrix. The moderate increase of capacity of carbon materials modified by plasma has been observed using symmetric two-electrode systems. Whereas investigations made in three-electrode system proved that the suitable selection of plasma modification parameters allows to obtain promising negative and positive electrode materials for supercapacitor application.  相似文献   
47.
The chemical composition of oil obtained from Pinus sibirica was investigated. The nonpolar lipids were the predominant lipid fraction while the triacylglycerols were the major component of this fraction. α‐ and γ‐tocopherols were the dominant tocopherols in pine oils. Eleven fatty acids (FA) were identified in pine nut oil. The unsaturated FA comprised over 90% of the total FA. Of these, polyunsaturated FA accounted for 66% of the total FA. 18:2 and 18:3 acids were the dominant unsaturated FA, while palmitic and stearic acids were the major saturated FA. Three unusual FA, namely 10,13‐octadecadienoic, gorlic and 11,13‐eicosadienoic acid, were tentatively identified in pine nut oil.  相似文献   
48.
49.
When V. V. Nalimov in his important book Naukometriya (Moskva 1969) postulated research on the process of developement of science with the aid of quantitative methods, he listed many different indicators. There were among them the number and growth of scientific publications — books and periodicals, the number of scientists, the level of expenditure. This article shows that the importance of these indicators was recognised by earlier authors. This revised version was published online in June 2006 with corrections to the Cover Date. This revised version was published online in June 2006 with corrections to the Cover Date. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
50.
The studies aimed to determine the occurrence and formation of nitrosamine contamination levels with dimethylnitrosamine (DMNA) and diethylnitrosamine (DENA) in meat of various kinds, species and genders of farm animals slaughtered at meat processing plants all over Poland. The meat after cooling, cutting and jointing was classified, then comminuted and divided into several experimental variants. Moreover, the effect of the most frequent functional additives used in food industry, such as sodium chloride and sodium ascorbate, and baking process upon the level of the meat pollution was researched. Nitrosamine (DMNA and DENA) concentrations were assessed by Varian 3400 gas chromatograph coupled with Finnigan MAT ITD 800 spectrometer. The quantitative and qualitative states of respective nitrosamines were determined by comparing the chromatogram values.  相似文献   
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